Volcano Irazu

Background Information:

Irazu is Costa Rica' s highest active volcano at 3432 m (or 11,260ft). It's name means Point Thunder. Irazu is a type of stratovolcano, which means it is a conical volcano built up by many layers of volcanic eruption materials, such as magma. In the national park, there are five total craters with the two most popular ones being Crater Principal and Diego de La Haya. Diego de La Haya is named after the person who recorded its first eruption in the 1700s. The national park was founded in 1965. Two years prior to this, John F. Kennedy (then U.S. President)   arrived in the Costa Rica the day of one of its most recent eruptions. The park is 5705 acres and contains both primary and secondary montane forests.

My professor and classmate Charlie hanging out on the fence in front of the crater

The Field Trip:

The field trip started at 8:00 am with a 4×4 taxi ride through the central valley through to the volcano. The last town we passed before heading up the mountain was Cartago. This is the most eastern city in the central valley and is the old capitol of Costa Rica.

As we were on our way to the crater, we passed many agricultural fields. These fields were growing onions, carrots, garlic, and cabbages. Most of the onions in Costa Rica are grown on Irazu. Agriculture is abundant in this region because the ash and magma from the previous volcanic eruptions makes the soil incredibly fertile. For this same reason, the farms stretched almost all the way to the crater of this active volcano.  Agriculture wasn't the only noticable changes as we climbed elevation.

As we gained elevation, I noticed significant changes in the vegetation. At the base of the volcano, despite being in the middle of the city, I saw that the plants were similar to those in San Ramon and more characteristic of a typical Costa Rican rainforest. About halfway up the top, I noticed this type of vegetation starting to give way to tall and sparsely dense oak trees. At the top of the volcano, the vegetation was more and unlike with a different style of leaves and they grew closer to the ground. Some species I noted were poor man's umbrella, dandelions, clover, and ferns. There was one plant that was covered in a black substance, but we never figured out what this was.

A cool plant we saw in Playa Hermosa

The biodiversity in animal species was not as great at the top of the volcano as it was at the bottom. We did see some endemic species of birds though. We saw alpine hummingbirds, a type of robin, and a couple types of sparrows. Supposedly there are also Coatis, but we never saw any. I noticed that I did not see many insects or bugs either. We did see tons of humans though.

Once at the park, we visited two main craters. The first place we went was the highest point of the volcano. This area was very rocky with sparse vegetation. The temperature was fairly chilly (probably around 45-50°F) and pretty cloudy. We could see down to the main crater, but nothing past the volcano. Supposedly, on a clear day, you can see both oceans from this point. As we walked down to the main craters, we looked more at the vegetation and saw a lot of plants we wouldn't normally see at lower altitudes.

My classmates and I at the tallest point of the volcano (3432 meters!)

After walking down a small hill, we reached the two main craters. The Diego de La Haya crater looked like a sandy patch, similar to the one we were standing on. It was definitely a crater though, because the walls surrounding it were high with almost no vegetation. The main crater was structured similarly, but with a pretty turquoise lake in the middle. This lake was incredibly clear and you could see the rocks underneath the water, even from far away. The sides of the crater were really interesting too because I could see the different rock layers and when/how they formed.

Diego de la Haya crater

Another interesting feature of the park was Plays Hermosa. This translates to Sister Beach and is probably called this because of the volcanic ash and sediment that collected and looks like a black sand beach. I had a really great time looking at the rocks and trying to identify them. Along the border of this "beach" was more vegetation. We explored this area and saw massive poor man's umbrella plants. We concluded the trip by looking at the crater once more and then eating lunch outside the gift shop.

Giant "poor man's umbrellas" with my professor and classmate for scale 

More Pictures:

Us goofing off on a school trip 

Playa Hermosa

I built a rock tower out of volcanic rocks. It was kicked over shortly after this picture was taken

My friend Jordan and I at Crater Principal

Information about the main crater

All smiles :)